The present invention relates to apparatus for manipulating cigarettes, cigars, cigarillos, filter rod sections or other rod-shaped articles which constitute or form part of smokers' products. More particularly, the invention relates to improvements in apparatus for changing the spacing between rows of elongated articles which move sideways. Apparatus of the just outlined character are normally employed in machines for the manufacture of filter-tipped smokers' products wherein tobacco-containing rod-shaped articles of pairs of such articles must be positioned at a predetermined distance from each other to provide room for insertion of filter rod sections therebetween.
The customary way of changing the distance between a pair of coaxial rod-shaped articles which move sideways is to cause the inner or the outer end faces of the articles to move along suitably inclined cams which compel the articles to move apart or nearer to each other. As a rule, the articles are held by suction in and extend from flutes or analogous receiving means so that the exposed portions of their end faces can be engaged by convergent or divergent cams. Such mode of changing the spacing between pairs of articles is acceptable as long as the articles are not transported at a relatively high speed. However, when the cams are to change the spacing between pairs of cigarettes which issue from a high-speed cigarette making machine, the cam-engaging portions of the end faces of cigarettes are likely to be defaced and/or damaged.
Other proposals to change the spacing between coaxial cigarettes or analogous smokers' products include the provision of two pairs of frustoconical fluted drums which are disposed between cylindrical article-receiving and cylindrical article-removing drums. Reference may be had to commonly owned U.S. Pat. No. 3,372,702 to Bohn et al. The bases of each pair of frustoconical drums are remote from each other. Such apparatus are reliable and do not deface or damage the articles because the flutes need not move relative to the articles or vice versa. However, the apparatus must comprise a large number of drums as well as complex and hence expensive bearings and drive means for the frustoconical drums.
Commonly owned U.S. Pat. No. 3,199,418 to Schubert discloses a further apparatus wherein the distance between neighboring rows of cigarettes or the like is changed by sets of fluted disks whose planes are inclined with respect to each other. The patented apparatus is suited practically exclusively for manipulation of relatively sturdy and rather short filter rod sections because the fact that the inclination of filter rod sections changes during transfer onto or from the disks does not affect their appearance and/or integrity. Manipulation of cigarettes (even relatively short cigarettes of unit length) in such apparatus is impractical or plain impossible because the weak and highly sensitive wrappers of cigarettes would be destroyed during transfer onto or from the respective sets of mutually inclined disks. Another drawback of the just described apparatus, as well as of the previously described apparatus, is that they cannot be readily converted for the manipulation of shorter or longer rod-sahped articles and/or for changing the extent to which the rows of rod-shaped articles are moved nearer to or further away from each other. This reduces the versatility and contributes to the cost of machines (particularly filter cigarette makers) wherein the apparatus are put to use. Each and every conversion necessitates the replacement of previously used pairs of frustoconical drums or sets of mutually inclined disks with different drums or disks.